Pg. 58-61 Autumn flush control for the cultivar ‘Early Delight’

Autumn flush control with ethephon is an important orchard management practice to ensure good flowering and cropping. Flush growth just before and during the flower induction period can lead to reduced crops, as these shoots will not mature in time to produce flowers. Due to new cultivars being planted in the South African litchi industry, flush control has to be re-evaluated for each cultivar due to their different sensitivities to ethephon. ‘Early Delight’, for example, a new early cultivar that is increasingly planted, appears to be more sensitive to ethephon. In order to determine the optimum concentrations as well as to register ethephon for use on ‘Early Delight’, trials were carried out in 2014 and 2016 with concentrations between O and 1000 ppm. Applications were done during April as spot sprays as per current industry practice for ‘Mauritius’ and ‘McLean’s Red’. The results showed that 500 ppm with the addition of a wetter is most successful in removing autumn flush and increasing yield in ‘Early Delight’. Lower concentrations than 500 ppm are less effective and higher concentrations may lead to phytotoxicity.